Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
xa hanh » xa thanh, xa khanh, va hanh
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
ca viet » va viet, co viet, hoa viet
va cam » va cham, va cac, va cao
xuc xa » tuc xa, buc xa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky ((nang xa) OR (nang ma)) hoi. hieu va cam xuc xa hanh vi ((cua tre) or (ca viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (nang ma)) hoi. hieu va cam xuc xa hanh vi ((cua tre) OR (ca viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang xa) OR (nang ma)) hoi. hieu va cam xuc xa hanh vi ((cua tre) or (ca viet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) OR (nang ma)) hoi. hieu va cam xuc xa hanh vi ((cua tre) or (ca viet))*.